The present invention relates to optical fiber arrays, in which a plurality of coated optical fibers are arranged, the optical fiber arrays being widely used in optical components, optical system, and the like, and particularly relates to optical fiber arrays having the end face of the coated optical fibers arranged in two dimensions, and furthermore, the present invention relates to optical components, such as an optical switch, using the optical fiber array.
In order to transmit and receive a large capacity of information at high speed, the optical fiber communications system has received attention. Today, coated optical fibers are installed not only between base stations in a big city, but even to terminals of each office building and each home, and dense optical fiber networks have been currently established. In relay points in the optical fiber network, a plurality of coated optical fibers are put together and the connection and switching of optical paths are carried out. In carrying out these connection and switching, the coated optical fibers are connected to filter elements or switching elements. In this case, the coated optical fibers are not fixed individually, but as an optical fiber array having the coated optical fibers arranged therein a plurality of coated optical fibers are handled and fixed simultaneously, thereby improving the working efficiency.
Although the conventional optical fiber array is a one-dimensional optical fiber array having coated optical fibers arranged as to align the end faces of the coated optical fiber in a line, high density arrangement is demanded due to an increase in the channel capacity and to the miniaturization of elements in recent years, and a two-dimensional optical fiber array having the end faces of coated optical fibers arranged in two dimensions is desirable.
As for the structure of the two-dimensional optical fiber array, it is known that three substrates are used for holding the optical fiber array (for example, U.S. Pat. No. 6,690,875 (FIG. 4, columns 6-7)). In U.S. Pat. No. 6,690,875 (FIG. 4, columns 6-7), an optical fiber inclined by an angle α is inserted into a hole of a housing entry substrate, and a coating portion of the coated optical fiber is bent by means of a hole of an angle alignment substrate, and then an optical fiber portion of the coated optical fiber, the optical fiber portion being exposed by removing the coating, is inserted into a hole (aperture) of a primary substrate and is fixed.
As for other structure of the two-dimensional optical fiber array, it is known that two substrates are used for holding fibers (for example, U.S. Pat. No. 5,135,590 (FIG. 1, columns 3-5). In U.S. Pat. No. 5,135,590 (FIG. 1, columns 3-5), the optical fiber of an coated optical fiber is passed through a hole (aperture) of a guiding plate, and the tip of the optical fiber of the coated optical fiber is passed through a hole (aperture) of a securing plate and is fixed.
As for other structure of the two-dimensional optical fiber array, it is known that three substrates are used for holding the optical fiber of a fiber (for example, U.S. Pat. No. 6,633,719 (FIG. 6, FIG. 7, from line 55 in column 5 to line 19 of column 6). In the method of U.S. Pat. No. 6,633,719 (FIG. 6, FIG. 7, from line 55 in column 5 to line 19 of column 6), the optical fiber of an coated optical fiber is passed through each hole of a front plate, a back plate, and a third plate, and the back plate is offset (translated), so that the optical fiber is clamped by the inner walls of the holes, and is then adhered and fixed.
As for other structure of the two-dimensional optical fiber array, it is known that one substrate is used for holding the optical fiber of a fiber (for example, JP-A-2004-271656 (FIGS. 1-3, pp. 6-8). In JP-A-2004-271656 (FIGS. 1-3, pp. 6-8), the optical core of an coated optical fiber is inserted into a through-hole of an optical fiber array substrate and is fixed.